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Does Profiling Work?

Bruce Schneier, a security technologist and author of several books on computer security, says no.

There are two kinds of profiling. There’s behavioral profiling based on how someone acts, and there’s automatic profiling based on name, nationality, method of ticket purchase, and so on. The first one can be effective, but is very hard to do right. The second one makes us all less safe. The problem with automatic profiling is that it doesn’t work.

Terrorists don’t fit a profile and cannot be plucked out of crowds by computers. They’re European, Asian, African, Hispanic, and Middle Eastern, male and female, young and old. Umar Farouk Abdul Mutallab was Nigerian. Richard Reid, the shoe bomber, was British with a Jamaican father. Germaine Lindsay, one of the 7/7 London bombers, was Afro-Caribbean. Dirty bomb suspect Jose Padilla was Hispanic-American. The 2002 Bali terrorists were Indonesian. Timothy McVeigh was a white American. So was the Unabomber. The Chechen terrorists who blew up two Russian planes in 2004 were female. Palestinian terrorists routinely recruit “clean” suicide bombers, and have used unsuspecting Westerners as bomb carriers.

Without an accurate profile, the system can be statistically demonstrated to be no more effective than random screening.